JP2018169310A - Terminal position estimation device, program and method in which mobile object recognition information is taken into account - Google Patents

Abstract

To provide a device with which it is possible to more accurately estimate the position of a terminal having received a radio wave from a radio wave source taking into account a movable object also.SOLUTION: The present device is a terminal position estimation device for acquiring received radio wave information at a terminal and estimating the position of the terminal, comprising: object distribution determination means for acquiring object recognition information from object recognition means capable of recognizing a movable object and determining, on the basis of this object recognition information and information pertaining to the arrangement of previously installed objects, an object distribution representing the distribution of the movable object and the previously installed objects; radio wave source selection means for performing radio wave simulation with regard to the determined object distribution and selecting an appropriate radio wave source suitable for terminal position estimation from among a plurality of arranged radio wave sources having been previously arranged; and terminal position determination means for determining the terminal position using information, out of the received radio wave information having been acquired, that pertains to a plural number among the selected appropriate radio wave sources.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a technique for estimating the position of a terminal based on the reception status of radio waves at the terminal.

  Conventionally, a technique for estimating the position of a receiving terminal using a plurality of received radio signals (radio waves) has become widespread. For example, positioning technology using outdoor GPS (Global Positioning System), indoor wireless LAN (Local Area Network), and the like are widely used at present.

  In such positioning technology using radio waves, whether there is an object that affects radio wave propagation between the radio wave source (radio wave source) such as satellite, base station or access point and the terminal, Positioning results are greatly affected. For example, when a shielding object that shields radio waves is interposed, the received signal strength at the terminal is lower than when radio waves reach the terminal directly, and the distance between the radio wave source and the terminal is estimated to be larger than actual, The error of position estimation will increase.

  For such problems, the system disclosed in Non-Patent Document 1 is different from the radio wave attenuation model used when a static shield with a fixed position is present between the transmitting and receiving nodes and is not present. By using the model, the position estimation accuracy is improved. In addition, by estimating the position estimation error by radio wave simulation considering the influence of the shielding object, and determining the position of the transmission node so that the expected error is small, the optimal transmission node arrangement according to the shielding object You can get.

  Furthermore, Patent Document 1 discloses that when there is an obstacle for radio wave transmission between radio wave transmitters / receivers, the radio signal between the radio transmitter / receiver unit is not based on the radio characteristic parameter between the radio transmitter / receiver unit and the radio terminal. A technique for estimating the position of a wireless terminal from a change detection result of a radio wave propagation environment by communication is disclosed. In this technique, when radio waves are shielded, priority (likelihood) used for position estimation is set for each transmitter.

JP 2011-203129 A

Okaumi, Masaki Igarashi, Hideaki Uchiyama, Takashi Shimada, Hajime Nagahara, Rinichiro Taniguchi, “Anchor Node Placement Considering Shielding in Wireless Location Estimation”, Multimedia, Distributed, Cooperation and Mobile (DICOMO2015) Symposium, 2015 799-802

  In the conventional technology including the technology described above, although the object that affects the propagation of radio waves is taken into consideration, the object considered is a static shield / obstacle with a fixed position to the last. . However, in actual terminal location estimation, it is often the case that a person cannot be ignored as an object that interferes with radio wave (radio signal) propagation.

  For example, in stores in various fields, there is a growing need for accurately grasping the flow lines of customers who have terminals and store staff. In this case, it is common to estimate the terminal position by arranging a plurality of beacon transmission sources (hereinafter abbreviated as beacons) in the store. Here, as a matter of course, the person moving in the store greatly affects the terminal position estimation by these beacons.

  However, in the prior art including the above-described technique, such a person cannot be considered as an object that affects the propagation of radio waves. As a result, an increase in error in the terminal position estimation result becomes a problem. Thus, although the influence on the radio wave propagation by a movable object including a person is great, it has not been considered in the past.

  Accordingly, an object of the present invention is to provide an apparatus, a program, and a method that can estimate the position of a terminal that has received a radio wave from a radio wave source with higher accuracy in consideration of a movable object.

According to the present invention, there is provided a terminal position estimation device that acquires received radio wave information in a terminal that has received radio waves from a radio wave source and estimates the position of the terminal,
Object recognition information from an object recognition unit capable of recognizing a movable object is acquired, and the movable object and the preinstalled object are set based on the object recognition information and the arrangement information of the preinstalled object. An object distribution determining means for determining an object distribution which is an object distribution;
A radio wave source selecting means for performing a radio wave simulation on the determined object distribution and selecting a suitable radio wave source suitable for position estimation of the terminal from a plurality of pre-arranged radio wave sources;
A terminal position estimation device is provided that includes terminal position determination means for determining the position of the terminal using information related to a plurality of selected suitable radio wave sources from the acquired received radio wave information.

  As one embodiment of the terminal position estimating apparatus according to the present invention, the radio wave source selecting means is configured such that the object distribution at one time related to position estimation does not change by a predetermined amount or more compared to the object distribution at the previous time. In this case, the preferred radio wave source selected at the previous time is preferably used as the preferred radio wave source at this one time.

  Further, as another embodiment of the terminal position estimation apparatus according to the present invention, a radio wave source that performs radio wave simulation on at least an object arrangement related to the arrangement information of an object installed in advance and minimizes an error in the estimated position of the terminal It is also preferable to further include radio wave source arrangement means that decides the arrangement and determines an arrangement position where a plurality of arrangement radio wave sources are arranged in advance from candidate positions where radio wave sources can be installed based on the determined arrangement. .

  Furthermore, as yet another embodiment of the terminal position estimating apparatus according to the present invention, the radio wave source selecting unit may select all of the plurality of arranged radio wave sources when there is no movable object at one time related to position estimation. It is also preferable to use a suitable radio wave source at this one time.

  As a specific form of the preferred radio wave source selection process, the radio wave source selection means performs radio wave simulation using maximum likelihood estimation for each arrangement pattern of a plurality of arrangement radio wave sources for the determined object distribution. A radio wave that calculates an estimated probability of the estimated position of the terminal, generates a cost function related to the calculated estimated probability and a distance between the estimated position and the true position, and minimizes the generated cost function It is also preferable to determine the arrangement of the sources and select the suitable radio wave source based on the determined arrangement.

  Furthermore, as still another embodiment of the terminal position estimation device according to the present invention, the terminal position determination means further selects three of the selected suitable radio wave sources in order from the highest received radio wave intensity, It is also preferable to determine the position of the terminal by three-point positioning using three radio sources. Alternatively, the terminal position determining means preferably determines the position of the terminal by maximum likelihood estimation by a plurality of the selected suitable radio wave sources.

  The object recognition means preferably generates the object recognition information based on photographing or measurement information from at least one of a camera, an omnidirectional camera, a depth camera, a laser positioning means, and a thermography means.

According to the present invention, there is also provided a program for causing a computer mounted in a device that acquires received radio wave information in a terminal that has received radio waves from a radio wave source and estimates the position of the terminal to function.
Object recognition information from an object recognition unit capable of recognizing a movable object is acquired, and the movable object and the preinstalled object are set based on the object recognition information and the arrangement information of the preinstalled object. An object distribution determining means for determining an object distribution which is an object distribution;
A radio wave source selecting means for performing a radio wave simulation on the determined object distribution and selecting a suitable radio wave source suitable for position estimation of the terminal from a plurality of pre-arranged radio wave sources;
Provided is a terminal position estimation program that causes a computer to function as terminal position determining means for determining the position of the terminal using information related to a plurality of selected suitable radio wave sources from the acquired received radio wave information Is done.

According to the present invention, there is further provided a terminal position estimation method by a computer installed in an apparatus for acquiring received radio wave information at a terminal that has received radio waves from a radio wave source and estimating the position of the terminal,
Object recognition information from an object recognition unit capable of recognizing a movable object is acquired, and the movable object and the preinstalled object are set based on the object recognition information and the arrangement information of the preinstalled object. Determining an object distribution that is an object distribution;
Performing a radio wave simulation on the determined object distribution, and selecting a suitable radio wave source suitable for position estimation of the terminal from a plurality of pre-arranged radio wave sources;
There is provided a terminal position estimation method including a step of determining the position of the terminal using information related to a plurality of the selected suitable radio wave sources among the acquired received radio wave information.

  According to the terminal position estimation apparatus, program, and method of the present invention, it is possible to estimate the position of a terminal that has received a radio wave from a radio wave source with higher accuracy in consideration of a movable object.

It is a schematic diagram which shows one Embodiment of the terminal location estimation system containing the terminal location estimation apparatus by this invention. It is a functional block diagram which shows the function structure in one Embodiment of the terminal position estimation apparatus by this invention. It is a flowchart which shows one Embodiment of the terminal position estimation process in a radio wave source selection part and a terminal position determination part. It is a flowchart which shows one Embodiment of the suitable radio wave source selection process in a radio wave source selection part.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[Terminal position estimation system]
FIG. 1 is a schematic diagram showing an embodiment of a terminal location estimation system including a terminal location estimation apparatus according to the present invention.

  The terminal position estimation system according to the present embodiment shown in FIG. 1 estimates the momentary position in one store in at least one terminal 3 possessed by a store clerk or a customer, and the store clerk who owns the terminal 3 It is possible to grasp the flow line in the store for customers and customers.

Specifically, this terminal location estimation system
(A) Beacon 2 installed at a plurality of positions in the store and transmitting radio waves at predetermined time intervals in all directions;
(B) one or a plurality of cameras 4 capable of photographing a movable object such as a person and transmitting information of the photographed image in time series via a wireless or wired communication network;
(C) “Object recognition information” is generated from a time-series image group acquired from the camera 4 via the communication network, and further directly (or via a relay device such as an access point) from the terminal 3 via the wireless communication network. ) It is provided with a terminal position estimation device 1 that acquires “received radio wave information”, estimates the position of the terminal 3 every moment based on the generated / acquired information, and determines the flow line in the store.

  Here, objects that affect radio wave propagation such as desks, chairs, partitions, exhibition stands, and counters are arranged in the store. The terminal position estimation apparatus 1 also acquires the arrangement information (“object arrangement information”) of an object previously installed in the store and uses it for position estimation of the terminal 3. This “object arrangement information” may also be generated after recognizing an installed object based on an image group from the camera 4. As a result, for example, even if the layout of equipment in the store is changed or temporarily placed, “object arrangement information” that accurately corresponds to the layout can be obtained.

  The beacon 2 can be a BLE (Bluetooth (registered trademark) Low Energy) specification beacon that transmits an advertisement packet in all directions at intervals of 100 to 1000 msec. Of course, the beacon 2 is not limited to this. For example, it can be used as a wireless LAN access point such as Wi-Fi (registered trademark), and the terminal 3 can receive radio waves therefrom and generate “received radio wave information”. Then, various radio wave sources can be adopted as the beacon 2.

  Incidentally, the installation position of the beacon 2 as shown in FIG. 1 (the arrangement of the beacon 2 in the store) is determined by the terminal position estimation device 1 using the captured image data from the camera 4 as will be described in detail later. Also good.

  Furthermore, in the present embodiment, the terminal 3 is a smartphone, a mobile phone, a tablet computer, a wearable terminal, or the like that can be carried by a store clerk, a customer, or the like. Applicable. The terminal 3 can simultaneously receive radio waves transmitted from a plurality of (preferably three or more) beacons 2.

Similarly, the terminal position estimation apparatus 1 shown in FIG. 1 is an apparatus that acquires “received radio wave information” in the terminal 3 that has received radio waves from the beacon 2 that is a radio wave source, and estimates the position of the terminal 3. Specifically, as its characteristics,
(A) Acquiring “object recognition information” from an object recognition means capable of recognizing a movable object, and based on this “object recognition information” and “object arrangement information” of a previously installed object, An object distribution determining unit 113 that determines an object that can move and an “object distribution” that is a distribution of the previously installed object;
(B) A radio wave simulation is performed on the determined “object distribution” to determine an arrangement of radio wave sources that minimizes an error in the estimated position of the terminal 3, and a plurality of pre-arranged multiples based on the determined arrangement A radio wave source selection unit 114b that selects a “preferred radio wave source (preferred beacon)” suitable for estimating the position of the terminal 3 from the beacon 2 that is an arrangement radio wave source of
(C) Of the acquired “received radio wave information”, the terminal position determination unit 116 that determines the position of the terminal 3 using information related to a plurality of selected “preferred radio wave sources (preferred beacons)” Have.

  Here, the “received radio wave information” is, for example, information in which the reception time and received signal strength (Received Signal Strength Indicator, RSSI) in the radio wave received by the terminal 3 from the beacon 2 are associated with the identifier of the beacon 2. Can do. Further, the “object arrangement information” may be, for example, position coordinates or a position coordinate range of an object arranged in advance. Further, the “object recognition information” can be, for example, the foot position coordinates of the recognized person at each time.

  As described above, as shown as configurations (A) to (C), the terminal position estimation apparatus 1 uses a “preferred radio wave source (preferred beacon)” for determining the position of the terminal 3 for “ The selection is made in consideration of not only the “object placement information” but also “object recognition information” about a movable object such as a person. As a result, even if a moving person or the like affects the propagation of radio waves from the beacon 2 to the terminal 3, it is possible to reliably capture the influence and estimate the position of the terminal 3 with higher accuracy.

  Further, for example, “object distribution” is determined based on “object recognition information” and “object arrangement information” at each time in the position estimation period, and “preferred radio wave source (preferred beacon)” is selected at each time. Thus, the position of the terminal 3 can be estimated every moment. Thereby, the position of each terminal 3 can be determined with higher accuracy even in a situation where, for example, a large number of persons are moving around in the store.

  In the present embodiment, the object recognition means in the configuration (A) recognizes an object that can be moved by acquiring captured image data from the camera 4 and generates “object recognition information” in FIG. Part 111 is formed. As this change mode, an object recognition means (object recognition unit 111) may be provided in an external device, and the terminal position estimation device 1 may acquire “object recognition information” from this device.

  As yet another embodiment, the object recognition means is based on imaging or measurement information from at least one of an omnidirectional (omnidirectional) camera, a depth camera, an infrared camera, an infrared positioning means, a laser positioning means, and a thermographic means. Based on this, “object recognition information” may be generated. For example, the depth value information (for each target pixel) generated by the depth camera can be converted into image data and used in the same manner as a captured image by the camera 4. In any case, the terminal position estimation apparatus 1 can acquire “object recognition information” generated by some means and use it for position estimation of the terminal 3.

  In addition, a movable object as a recognition target related to the “object recognition information” can be recognized by an object recognition unit such as a person, an animal, a vehicle, or other movable physical target (for example, photographed by the camera 4). Various things apply (if possible). Also, the shooting location is not particularly limited. For example, in addition to the inside of a store, it may be indoors such as a company, a school, a hall, or the inside of a house. It may be outdoors where shoppers, workers, pedestrians, runners, etc. can be reflected.

  Furthermore, as still another embodiment, the terminal 3 includes the above-described configurations (A) to (C), and functions as a terminal position estimation device that estimates its own position and further the positions of other terminals 3 around it. May be. In this case, for example, the “object recognition information” can be generated using a camera built in the terminal 3 (position is determined every moment).

[Device configuration, terminal location estimation method]
FIG. 2 is a functional block diagram showing a functional configuration in an embodiment of the terminal position estimation apparatus according to the present invention.

  According to FIG. 2, the terminal position estimation apparatus 1 includes a communication interface 101 that can be connected to the camera 4, the terminal 3, and the like, a received radio wave information storage unit 102, an object recognition information storage unit 103, and an object arrangement information storage unit. 104, a terminal flow line information storage unit 105, a display keyboard (DP / KB) 106, and a processor memory. Here, the processor memory realizes the terminal position estimation function by executing a program that causes the computer of the terminal position estimation apparatus 1 to function.

  Further, the processor memory has a radio wave source determination including an object recognition unit 111, an object recognition information management unit 112, an object distribution determination unit 113, a radio wave source arrangement determination unit 114a, and a radio wave source selection unit 114b as functional components. Unit 114, received radio wave information management unit 115, terminal position determination unit 116, terminal flow line information management unit 117, communication control unit 118, and input / output control unit 119. Note that the processing flow shown by connecting the functional components of the terminal location estimation apparatus 1 in FIG. 2 with arrows is understood as an embodiment of the terminal location estimation method according to the present invention.

  Similarly, in FIG. 2, the camera 4 is a visible light, near-infrared, or infrared-capable imaging device including a solid-state imaging device such as a CCD image sensor or a CMOS image sensor. Further, the camera 4 or a camera control device (not shown) generates captured image data including an image of an object captured by the camera 4 and transmits the information to the object tracking device 1 in time series or batch. It has a function.

  The communication interface 101 receives captured image data that is a time-series image group from the camera 4 or the camera control device via a wired or wireless communication network. The acquired captured image data (image file) is output to the object recognition unit 111. The communication interface 101 receives received radio wave information from the terminal 3 directly (or via a relay device such as an access point) via the wireless communication network. Alternatively, the received radio wave information may be received after being connected to the terminal 3 via a USB (Universal Serial Bus) or the like. Further, the communication interface 101 may transmit the flow line information generated as a result of the terminal position estimation to an external information processing apparatus. In addition, transmission / reception of these information in the communication interface 101 is controlled by the communication control unit 118, and information is exchanged at an appropriate timing.

  In this embodiment, the object recognizing unit 111 recognizes a person staying or moving in the store based on the captured image data related to the image captured by the camera 4, and generates object (person) recognition information. Here, the generated object (person) recognition information may include two-dimensional (or three-dimensional) coordinate values of the foot position of one or more recognized persons at each time of recognition processing. Good. Note that the object (person) recognition process in the object recognition unit 111 can be performed by employing various known methods.

  For example, when an omnidirectional camera is used as the camera 4, Tatsuya Kobayashi, Haruhisa Kato, Masaru Sugano, “Proposal of a person flow tracking technique robust to occlusion using a monocular omnidirectional camera”, Shingaku It is possible to generate object (person) recognition information using the technique described in Technical Bulletin, vol.116, no.411, PRMU2016-146, 2017, pages 321-326.

  Specifically, in this method, person detection processing and person tracking processing are executed for each image frame, the position of each person at each time is estimated, and the person is tracked. Among these, in the person detection process, matching is performed between a region extracted using the background difference technique and a 3D human model prepared in advance to detect a human region in the image. Here, a person model is arranged in advance at various foot positions where a person can exist, and the corresponding foot position is detected as a person position by searching for a contour having the highest similarity to the foreground region.

  Further, in the person tracking process, the person ID being tracked is assigned to the detected person area by associating the person being tracked with the above detection result, and the element having the maximum matching score by one-to-one person matching is determined. select. Next, based on the result of this person matching, the tracking position of each person is estimated using a particle filter.

  Incidentally, the present apparatus 1 does not include the object recognition unit 111, and the object recognition information management unit 112 may take an embodiment in which object recognition information is acquired and managed from an external object recognition unit. In any case, the object recognition information management unit 112 outputs the acquired momentary object recognition information to the object distribution determination unit 113 as appropriate while saving the object recognition information in the object identification information storage unit 103.

  Based on the input object recognition information and the input object arrangement information, the object distribution determination unit 113 determines the position distribution of a movable object (for example, a person) and a previously installed object (for example, equipment in a store). The object distribution is determined.

  Here, the object arrangement information is information including a coordinate value or a coordinate value range of an arrangement position for an object that affects radio wave propagation such as a desk, a chair, a partition, an exhibition table, or a counter in a store. It is also preferable that the data is input, recorded in the object arrangement information storage unit 104 via the input / output control unit 119, and output to the object distribution determination unit 113. It is also preferable that the object arrangement information further includes information related to the size (vertical and horizontal) of the floor in the store where the position is estimated. As a change mode, this object arrangement information may also be generated by the object recognition unit 111 recognizing an installed object in the store based on the captured image data related to the image captured by the camera 4.

  Similarly, in FIG. 2, the radio wave source arrangement determining unit 114a of the radio wave source determining unit 114 determines an arrangement position where the beacon 2 is actually arranged in advance from the candidate positions where the beacon 2 can be installed in the store. The pre-arrangement position determination process for the beacon 2 will be described in detail later. As a change mode, the device 1 does not have the radio wave source arrangement determining unit 114 a, and the arrangement information of the beacon 2 that is considered to be appropriate from a sense of experience or past experience is input / output from the keyboard 106. The power may be input to the power supply determination unit 114 via the control unit 119.

On the other hand, the radio wave source selection unit 114b of the radio wave source determination unit 114, as will be described in detail later with reference to FIGS.
(A) For the object distribution input from the object distribution determination unit 113, radio wave simulation using maximum likelihood estimation for each arrangement pattern (set of arrangement positions) A for a plurality of beacons 2 (arrangement radio wave sources) arranged in advance. Go to calculate the estimated probability of the estimated position e of the terminal 3,
(B) generating a cost function C (A) related to the calculated estimated probability and the distance between the estimated position e and the true position u;
(C) Determine the arrangement A _opt of the beacon 2 that minimizes the generated cost function C (A),
(D) Based on the determined arrangement A _opt , a suitable beacon 2 (preferred radio wave source) suitable for position estimation of the terminal 3 is selected from a plurality of beacons 2 (arranged radio wave sources) arranged in advance.

  The reception radio wave information management unit 115 manages the reception radio wave information acquired from the terminal 3 while inputting it and storing it in the reception radio wave information storage unit 102, and appropriately outputting it to the terminal position determination unit 116. Here, the received radio wave information can be information in which the reception time, the RSSI, and the identifier of the beacon 2 are associated with each beacon 2 that is the source of the radio wave received by the terminal 3.

The terminal position determination unit 116 determines the position of the terminal 3 by using information related to a plurality of preferred beacons 2 (preferred radio wave sources) selected by the radio wave source selection unit 114b from the acquired received radio wave information. To do. In particular,
(A) Of the selected preferred beacons 2, three may be further selected in order from the highest RSSI, and the position of the terminal 3 may be determined by three-point positioning using these three beacons 2, or
(B) The position of the terminal 3 may be determined by maximum likelihood estimation using a plurality of the selected preferred beacons 2.

  FIG. 3 is a flowchart illustrating an embodiment of the terminal location estimation process in the radio wave source selection unit 114b and the terminal location determination unit 116.

(S101) Object arrangement information (for example, installation position coordinates in equipment in a store) is acquired.
(S102) Acquire beacon arrangement information including an arrangement A _set of n beacons 2 arranged in advance and the number m of suitable beacons 2 to be selected.

  Next, a loop (steps S103 to S111) of a suitable beacon selection process and a terminal position determination process at each time in the position estimation period is entered. That is, the processes of steps S103 to S111 are executed at each time. Thereby, the position of the terminal 3 is determined (estimated) every moment.

(S103) Object (person) recognition information is acquired.
(S104) Object distribution information is generated from the object arrangement information and the object (person) recognition information.
(S105) It is determined whether or not there is an object (person) that is moving or can move. Here, when a false determination (determination that it does not exist) is performed, the process proceeds to step S107b.

(S107b) All of the n beacons 2 (arranged radio wave sources) installed in advance are set as preferred beacons 2 (preferred radio wave sources) at this time. This is particularly effective when the arrangement of these n beacons 2 is suitably determined in advance by the radio wave source arrangement determination unit 114a based on the object arrangement information. As another flow form, when step S107b is canceled and a false determination is made in step S105, it is possible to adopt a form in which the process proceeds to step S107a described later.

(S106) On the other hand, if a true determination (determination that exists) is made in step S105, then whether or not the position of the moving object (person) has changed, or It is determined whether or not the determined object distribution has changed.

  Here, the position has changed, for example, a predetermined range that includes a position at a predetermined distance away from the position at the previous time or a position at the previous time. It may be outside. Also, the object distribution is changing that the position of at least one object constituting the object distribution is separated by a predetermined distance or more from the position at the previous time, or one before. It may be outside the predetermined range including the position at the time.

If a false determination (determination that there is no change) is made in step S106, the process proceeds to step S107c.
(S107c) The preferred beacon 2 (preferred radio wave source) selected at the previous time is set as the preferred beacon 2 (preferred radio wave source) at this time. If there is no preferred beacon 2 selected at the previous time, the process proceeds to step S107a regardless of the determination result in step S106.

(S107a) On the other hand, when true determination (determination that it has changed) is performed in step S106, m preferred beacons 2 are changed from n beacons 2 arranged in advance using the maximum likelihood estimation method. select. This is a process of excluding the beacon 2 that is more strongly affected by a moving object or an object (person) that can move. This preferred beacon selection process will be described later in detail with reference to FIG.

(S108) Received radio wave information is acquired from the terminal 3.
(S109) Three of the selected preferred beacons 2 (preferred radio wave sources) are further selected in order from the one with the highest RSSI.

(S110) The position of the terminal 3 is determined by three-point positioning using these three beacons 2. Specifically, the distance distance from each beacon 2 of the terminal 3 is expressed by the following formula (1) distance = 10 ^ ((TxPower−RSSI) / 10d) (unit is meter (m))
The three-point positioning may be executed using the calculated three distance distances. In the above formula (1), RSSI is the intensity (RSSI) of the radio wave received from the beacon 2, and the unit is dBm. TxPower is RSSI measured at a position 1 m away from the beacon 2 and d is a constant representing the degree of radio wave attenuation.
(S111) The terminal position estimation result including the estimated position coordinates (two-dimensional or three-dimensional) in the terminal 3 is output.

  By executing the processing of steps S103 to S111 described above at each time during the position estimation period, the terminal position determination unit 116 can form time-series information of the estimated position coordinates of the terminal 3. .

  FIG. 4 is a flowchart showing an embodiment of a preferred radio source selection process in the radio source selector 114b. The flow shown in the figure corresponds to the processing in step S107a in FIG.

In the radio wave source selection unit 114b, first, object distribution information and beacon arrangement information (n beacon arrangements A _set and the number m of preferred beacons to be selected) are set. Also, A _i (A _i ⊂A _set , A ₀ = φ) is an arrangement pattern in which the beacons 2 are installed one by one in the arrangement pattern A _set of a plurality of beacons 2 (arranged radio wave sources) arranged in advance. . That is, the arrangement pattern A _p (p = 1, 2,..., M) is the arrangement of the beacon 2 whose position is determined up to the p-th beacon. Thereafter, the loop of steps S201 to S204 is repeated until the parameter i is incremented by 1 from zero and reaches m-1.

Of these, step S201 is repeated as a process in a loop (incrementing k by 1) for _k of the estimated position ek of the terminal 3 that can be taken in the position estimation range. S202 is repeated as a process in a loop (incrementing j by 1) for _{j at} the true position u _j of the terminal 3 that can be taken in the position estimation range.

(S201) For the set object distribution, the beacon 2 of the arrangement pattern A _i (⊂A _set ) and the terminal 3 at the true position u _j (j = 0, 1,..., U _j εS) A radio wave simulation using the maximum likelihood estimation method is performed, and the probability P (A _i , u _j , e _k ) that the estimated position is e _k (k = 0, 1,..., E _k ∈S) is calculated. calculate. Here, S (⊂R ² ) is a set of all coordinates of the position estimation range.

Incidentally, in this maximum likelihood estimation, the above probability P (A _i , u _j , e _k ) is assumed to be a normal distribution with mean μ and variance σ ² , the likelihood function L is obtained, and μ and By determining the variance σ ² , this probability P (A _i , u _j , e _k ) can be determined. In addition, in the above radio wave simulation, the radio wave attenuation of the object distributed according to the object distribution information used when determining the radio wave intensity uses a numerical value set in advance according to the assumed object (for example, human body). May be. Further, the transmission radio wave characteristics such as the transmission radio wave intensity in each beacon 2 of the arrangement pattern A _set may be set uniformly to a predetermined one that is normally used, or matched to the characteristics of the beacon that is actually installed. It is also preferable to set the

(S202) Next, after the loop processing for k including step S201 is completed, the following expression (2) E (A _i , u _j ) = Σ _ekεR | u _j −e _k | * P ( A _i , u _j , e _k )
The expected value E (A _i , u _j ) of the distance between the estimated position e _k and the true position u _j (ie, the estimated error of the estimated position) defined by In the above formula _(2), Σ ek∈R is the sum of all the estimated position e _k of the terminal 3 that can be taken by the position estimation range (summation).

(S203) Next, after the processing of the loop for j including the above step S202 is completed, the cost function C (A _i ) is further expressed by the following equation (3) C (A _i ) = Σ _ujεS E ( A _i , u _j )
And a cost function C (A _i ) for the arrangement pattern A _i is calculated. In the above equation (3), Σ _ujεS is the sum of all the true positions u _j of the terminal 3 that can be taken in the position estimation range. That is, the cost function C (A _i ) defined here is the sum of expected values of position estimation errors in the entire position estimation range.

(S204) The arrangement pattern A _i is evaluated based on the calculated cost function C (A _i ). Specifically, the placement position of the (i + 1) th beacon 2 placed under the placement pattern A _i is a _{i + 1} , and the following equation (4) a _{i + 1} = arg min C (A _i ∪ { a})
Is used to determine the arrangement position a _{i + 1} . In the above equation (4), arg min is calculated for all possible arrangement positions a (εA _set ). Using this arrangement position a _{i + 1} , the arrangement A _{i + 1} can be expressed by the following equation (5) A _{i + 1} = A _i ∪ {a _{i + 1} }
Sought by.

(S205) In this way, the arrangement positions a of the beacons 2 that minimize the defined cost function C (A _i ) are sequentially determined for all the parameters i, and finally the arrangement positions a _{1 to} a a _m m pieces of suitable beacon placement a _opt (= a _m) is determined. Next, a suitable beacon 2 is selected from a plurality of beacons 2 arranged in advance based on the preferred beacon arrangement _Aopt .

  As described above, in the radio wave source selection unit 114b, the radio wave source selection unit 114b is more strongly influenced by the shielding or the like by the moving object (person) from among the n beacons 2 arranged in advance. Excluded. Thereby, after this, the terminal position determination unit 116 can determine the position of the terminal 3 using the suitable beacon 2 that is more suitable for position determination, and as a result, the conventional method that does not consider the influence of shielding or the like by the moving object As a result, the terminal position estimation accuracy is considerably improved.

  Returning to FIG. 2, the radio wave source arrangement determining unit 114a of the radio wave source determining unit 114 performs the same processing as that performed by the radio wave source selecting unit 114b described above with reference to FIG. Is determined from among the candidate positions where the beacon 2 can be placed. Here, the candidate position in the store is, for example, a position on a wall surface in the store, a position on equipment such as a desk or a chair, and the like, and may not be set on the floor surface.

Specifically, the radio wave source arrangement determining unit 114a sets A _all (⊂S) as all the arrangements that can be set for the n beacons 2.
(A) A radio wave simulation using maximum likelihood estimation is performed for each arrangement pattern A (⊂A _all ) for a candidate position where the beacon 2 can be placed in the store, and the estimated probability P (A , u, e)
(B) generating a cost function C (A) related to the distance between the calculated estimated position e and the true position u;
(C) The arrangement A _set (⊂A _all ) of n beacons 2 that minimizes the generated cost function C (A) is determined.

As a result, an appropriate arrangement of the beacons 2 is determined in consideration of the arrangement of the objects installed in advance, which is the premise of the preferred beacon selection process in the radio wave source selection unit 114b. The processing in the radio wave source arrangement determining unit 114a is the same as that in the radio wave source selecting unit 114b, but the set of beacon arrangement candidate points input for processing is not A _opt but A _all Is different.

  Similarly, in FIG. 2, the terminal flow line information management unit 117 collects the estimated position coordinates of the terminal 3 at each time during the position estimation period determined by the terminal position determination unit 116, and the terminal 3 (the user who owns the terminal 3). For each identifier ID, flow line information in which time series information of the collected estimated position coordinates is associated is generated. Further, the terminal flow line information management unit 117 may store the generated flow line information in the terminal flow line information storage unit 105, and preferably displays the generated flow line information on the display 106 via the input / output control unit 119. You may transmit to an external information processing apparatus via the control part 118 and the communication interface 101. FIG.

  As described above in detail, according to the present invention, the preferred radio wave source for determining the position of the terminal is not only the object arrangement information of the object installed in advance, but also the object about a movable object such as a person. The selection is made in consideration of the recognition information. As a result, for example, even if a moving person or the like affects the propagation of radio waves from the radio wave source to the terminal, it is possible to reliably capture the influence and estimate the position of the terminal more accurately.

  Also, for example, by determining the object distribution based on the object recognition information and the object arrangement information at each time in the position estimation period, and selecting a suitable radio wave source at each time, estimating the position of the terminal every moment Can do. Therefore, for example, the position of each terminal can be determined with higher accuracy even in a situation where many persons are moving around.

  By the way, the configuration and method of the present invention can be applied to, for example, a monitoring system for monitoring a place where a large number of persons move, stay, and go in and out, as well as in one store, in a commercial / service facility, and further in a store. The present invention can be applied to various systems such as a marketing survey system for investigating the entrance / exit of a person on a street of a city, a break, watching a game, participating in an event, and the situation of movement.

  In the various embodiments of the present invention described above, various changes, modifications, and omissions in the technical idea and scope of the present invention can be easily made by those skilled in the art. The above description is merely an example, and is not intended to be restrictive. The invention is limited only as defined in the following claims and the equivalents thereto.

DESCRIPTION OF SYMBOLS 1 Terminal position estimation apparatus 101 Communication interface 102 Received radio wave information storage part 103 Object recognition information storage part 104 Object arrangement information storage part 105 Terminal flow line information storage part 106 Display keyboard (DP / KB)
111 object recognition unit 112 object recognition information management unit 113 object distribution determination unit 114 radio wave source determination unit 114a radio wave source arrangement determination unit 114b radio wave source selection unit 115 received radio wave information management unit 116 terminal position determination unit 117 terminal flow line information management unit 118 Communication control unit 119 Input / output control unit 2 Beacon (radio wave source)
3 Terminal 4 Camera

Claims (10)

A terminal position estimation device that obtains received radio wave information at a terminal that has received radio waves from a radio wave source and estimates the position of the terminal,
Object recognition information from an object recognition unit capable of recognizing a movable object is acquired, and the movable object and the preinstalled object are set based on the object recognition information and the arrangement information of the preinstalled object. An object distribution determining means for determining an object distribution which is an object distribution;
A radio wave source selecting means for performing a radio wave simulation on the determined object distribution and selecting a suitable radio wave source suitable for position estimation of the terminal from a plurality of pre-arranged radio wave sources;
A terminal position estimator for determining the position of the terminal using information related to a plurality of the selected suitable radio wave sources among the acquired received radio wave information; .   The radio wave source selection unit is configured to select a preferred radio wave source selected at the previous time when the object distribution at one time related to position estimation has not changed by a predetermined amount or more compared to the object distribution at the previous time. The terminal position estimation apparatus according to claim 1, wherein the terminal is a preferred radio wave source at the one time.   Conduct radio wave simulation on at least the object arrangement related to the arrangement information of the previously installed object, determine the arrangement of the radio wave source that minimizes the error of the estimated position of the terminal, and based on the determined arrangement, 3. The terminal position estimation apparatus according to claim 1, further comprising radio wave source arrangement means for determining an arrangement position in which the plurality of arrangement radio wave sources are arranged in advance from candidate positions where a source can be installed. .   The radio wave source selection means, when there is no movable object at one time related to position estimation, sets all of the plurality of arranged radio wave sources as preferred radio sources at the one time. Item 4. The terminal position estimation apparatus according to any one of Items 1 to 3.   The radio wave source selecting means calculates an estimated probability of the estimated position of the terminal by performing radio wave simulation using maximum likelihood estimation for each arrangement pattern of the plurality of arranged radio wave sources for the determined object distribution, Generate a cost function related to the calculated estimated probability and the distance between the estimated position and the true position, determine the location of the radio wave source that minimizes the generated cost function, and determine the determined location The terminal position estimation apparatus according to any one of claims 1 to 4, wherein the suitable radio wave source is selected on the basis of the above.   The terminal position determining means further selects three of the selected suitable radio wave sources in order from the highest received radio wave intensity and determines the position of the terminal by three-point positioning using the three radio wave sources. The terminal position estimation apparatus according to claim 1, wherein:   The terminal position according to any one of claims 1 to 5, wherein the terminal position determining means determines the position of the terminal by maximum likelihood estimation using a plurality of the selected suitable radio wave sources. Estimating device.   The object recognition unit is configured to obtain the object recognition information based on photographing or measurement information from at least one of a camera, an omnidirectional camera, a depth camera, an infrared camera, an infrared positioning unit, a laser positioning unit, and a thermography unit. The terminal position estimation apparatus according to claim 1, wherein the terminal position estimation apparatus generates the terminal position. A program that causes a computer mounted on a device that acquires received radio wave information in a terminal that receives radio waves from a radio wave source and estimates the position of the terminal to function,
Object recognition information from an object recognition unit capable of recognizing a movable object is acquired, and the movable object and the preinstalled object are set based on the object recognition information and the arrangement information of the preinstalled object. An object distribution determining means for determining an object distribution which is an object distribution;
A radio wave source selecting means for performing a radio wave simulation on the determined object distribution and selecting a suitable radio wave source suitable for position estimation of the terminal from a plurality of pre-arranged radio wave sources;
A terminal that causes a computer to function as terminal position determining means for determining the position of the terminal using information related to a plurality of the selected preferable radio wave sources among the acquired received radio wave information Position estimation program. A terminal position estimation method using a computer mounted on a device that acquires received radio wave information at a terminal that has received radio waves from a radio wave source and estimates the position of the terminal,
Object recognition information from an object recognition unit capable of recognizing a movable object is acquired, and the movable object and the preinstalled object are set based on the object recognition information and the arrangement information of the preinstalled object. Determining an object distribution that is an object distribution;
Performing a radio wave simulation on the determined object distribution, and selecting a suitable radio wave source suitable for position estimation of the terminal from a plurality of pre-arranged radio wave sources;
And determining the position of the terminal using information related to a plurality of the selected suitable radio wave sources from the acquired received radio wave information.

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